Turkey and the PKK were a hot topic in Whitehall over 20 years ago ... and the Kurds won't concede an inch. Given that Turkey is a proud Nation, it's little wonder that they will use any means to scratch that irritating spot on their southern border.
Sadly, their integrity/sense [i.e. Cyprus & Greece] and their general behaviour is unlikely to lead the West/Europe to welcome them with open arms into the EU, although they are slowly creeping ever closer. I suspect this latest revelation might [hopefully, IMO] set that back a bit.
R.O.G. ... agreed